Scots scientists help create largest 3D map of universe ever made

A team of Scottish researchers has helped create what they believe to be the largest map of the known universe ever.

The Dark Energy Spectroscopic Instrument (Desi), was used by scientists from the University of St Andrews alongside leading researchers from the University of California, Berkeley, and other teams from across 70 institutions.

The Desi is based at the Mayall telescope in Arizona and collects observations of millions of galaxies and quasars.

The Desi created a high-resolution, 3D map of the cosmos over the course of five years, with the intention of exploring dark energy, which scientists believe makes up the majority of the universe.

The experiment was launched in May 2021 and aimed to capture light from 34 million galaxies and quasars.

However, researchers were able to capture even more than they aimed to, with 47 million galaxies and quasars and 20 million stars contributing to the 3D map.

Rita Tojeiro, professor of Astronomy at the University of St Andrews, said: “There is no doubt of the huge impact that Desi is having on cosmology.

“What is also fantastic about Desi, in addition to being a revolutionary cosmology survey, is that this new, three-dimensional map is enabling world-class legacy science.

“Each of the 47 million galaxies and quasars that Desi observed tells a unique story.

“We can collect these individual stories to reveal the overarching narratives of how galaxies form and evolve through cosmic time.

“Because Desi is revealing the three-dimensional cosmic web in which galaxies live with unprecedented detail, we can now study how galaxies respond to cosmic structures around them in ways that have not been possible before.”

Researchers will now aim to better understand dark energy and dark matter, which scientists say accounts for most of the matter in the universe, but has never been physically detected.

Professor Tojeiro added: “I have been waiting for over 10 years for this cosmic map.

“Now it is here and we are lucky enough to extend it and make it even better.

“The level of detail is incredible, and the map is so rich with information. We will be exploring it for 10 years to come.”